The field of the invention relates generally to turbine engines, and more particularly, to removing heat from combustor components within turbine engines.
At least some known turbine engines include a forward fan, a core engine, and a power turbine. The core engine includes at least one compressor that provides pressurized air to a combustor wherein the air is mixed with fuel and ignited for use in generating hot combustion gases. Generated combustion gases flow downstream to one or more turbines that extract energy from the gas to power the compressor and provide useful work, such as powering an aircraft. A turbine section may include a stationary turbine nozzle positioned at the outlet of the combustor for channeling combustion gases into a turbine rotor downstream thereof. At least some known turbine rotors include a plurality of circumferentially-spaced turbine blades that extend radially outward from a rotor disk that rotates about a centerline axis of the engine.
In at least some known combustors, fuel and air are pre-mixed in the fuel nozzle to produce a lean combustion flame that reduces NOx emissions. In some known systems, NOx emissions are further reduced with the use of an airflow system that channels air through swirl vane assemblies and around nested fuel nozzles to reduce internal temperatures. In such systems, a fuel nozzle system channels the air/fuel mixture to the ignition zone for combustion. However, the use of fuel nozzle assemblies may undesirably increase the potential for auto-ignition or flashback of residual fuel that lingers in areas around the system. More specifically, without adequate cooling of the system structure, the potential for auto-ignition or flashback is increased. As such the operational lifetime of the fuel nozzle system may be shortened.